Field of the Invention
The invention relates to an earphone, and specifically relates to an in-ear earphone.
Description of Related Art
Along with the continuous improvement of technology, all of electronic products have been developed with a tendency to become lighter and more miniaturized, and the electronic products like smartphone, tablet computer, or notebook, etc., have become indispensable in daily life of human beings. For each of those aforementioned electronic products, in order to allow a user/listener to listen to the audio information provided by the electronic product without disturbing the other people around, an earphone has become a necessary accessory to the electronic product. Moreover, the earphone also provides a better audio transmission to the listener so that the listener can clearly hear and understand the content of the audio information, and especially, unlike the an unclear audio transmission through the air, the audio transmission of the earphone is not be affected while the listener is moving, such as exercising, driving, engaging in intense movements or being in a noisy environment.
In recent years, the size of the speaker unit used for generating sound inside the earphone becomes smaller and smaller, so the speaker unit that is used to be located at the auricular region of the external part of the ear canal is inserted into the narrow ear canal. As a result, the earphone becomes light and handy, and the power consumption may also be reduced. On the other hand, in order to prevent the stiff housing of the earphone from causing discomfort in the ear canal, the outside of the housing of the current earphone is sheathed with a soft earpad. However, as shown in FIG. 1, currently, the outside of a tube portion 12 extending into the ear canal of the housing 10 is sheathed with an earpad 22. When the earpad 22 and the tube portion 12 are inserted into the ear canal together, a portion used for sheathing the tube portion 12 and the portion used for contacting the ear canal wall of the earpad 22 are clamped between the ear canal wall and the tube portion 12. With regard to the narrow ear canal, the thickness of the two superimposed portions of the earpad 22 may cause a substantial pressure, such that the user may have an oppressive feeling after wearing the earphone. Otherwise, the portion used for sheathing the tube portion 12 of the earpad 22 is easily loosened because of material aging.